Police believe all of the victims were acquainted with the gunman.

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JONESBORO, Ark. (AP) - Police say a gunman who shot and killed three people and injured four in northeast Arkansas was an acquaintance or friend, but a motive is unknown.

Jonesboro Police Sgt. Doug Formon says the shooter was 40-year-old Porfirio Hernandez, who recently had been released from a mental health treatment facility. A 38-year-old man and a 12-year-old girl were killed Saturday afternoon at a home in Jonesboro, and four others were injured.

About 20 minutes later, police received a call about a shooting at a business, where a 31-year-old man was found dead. Hernandez was later found dead of an apparent self-inflicted gunshot wound.

Three people are in critical condition in Memphis, Tennessee, hospitals: a 43-year-old man, a 36-year-old woman and an 8-year-old boy. A 10-year-old boy is in stable condition.

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